Hypophthalmichthys molitrix The Asian Carp or (Hypophthalmichthys molitrix) is a very compressed silvery scaled fish that are toothless. Larger species have a stiff on the dorsal and anal fins as well as the end of its pectoral. There have been reports of a silver carp caught that weighed in at 1260 mm. They are at large four feet long and can grow to an astonishing 80 to 100 pounds.[1]
Detailed Description:
Bighead and silver carp have reproductive requirements similar to those of striped bass. There is a real potential to establish a reproducing population of Asian carp in Lake Texoma which could be devastating to striped bass fishery and paddlefish recovery efforts. The silver carp is a filter feeder, and possesses a remarkably specialized filtration apparatus capable of filtering particles as small as 4 µm. The gill rakers are fused into a sponge like filter, and an epibranchial organ secretes mucous which assists in trapping small particles. A strong buccal pump forces water through this filter. Silver carp, like all Hypophthalmichthys species, have no stomachs; they are thought to feed more or less constantly. Silver carp are thought to feed largely on phytoplankton; they also consume zooplankton and detritus. Because of their plankton-feeding habits, there is concern that they will compete with native planktivorous fishes, which include paddlefish Polyodon spathula, gizzard shad Dorosoma petenense and young fish of almost all species.[2] The silver carp unlike any other sea creatures has little or no predators around where they were let out near the United States. Silver carp are only predators that have no known predators around where they were sent to from Arkansas. This invasive species is very harmful to the food chain and is not a benefit what so ever. Although silver carp are very aggressive and are “taking over” the seas near our country there are a few other species of Asian carp that were also sent here to maintain phytoplankton population but it back lashed.
Habitat and Distribution:
All the above except large-scale silver carp have been cultivated in aquaculture in China for over 1,000 years. Large-scale silver carp, a more southern species, is native to, and is cultivated in Vietnam. Grass, silver, bighead and black carps are known as the "Four Domesticated Fish" in China and are the most important freshwater fish species for food and Chinese medicine. Bighead and silver carps are the most important fish, worldwide, in terms of total aquaculture production [1] . Common carp and crucian carp are also common food fishes in China and elsewhere. Goldfish, on the other hand, are cultivated mainly as pet fish.4 Because of their prominence, and because they were imported to the United States much later than the other species of freshwater fish, the term "Asian carps" is often used in the United States with the intended meaning of only grass, black, silver, and bighead carps. In the United States Asian carps are considered to be nuisance invasive species. Of the Asian carps that have been introduced to the United States, only two (crucian and black carps) are not known to be firmly established. Crucian carp is probably extirpated.[2] However, since 2003, several adult, fertile, black carp have been captured from the Atchafalaya and other rivers connected to the Mississippi River.[3] Dr. Leo Nico, in the book Black Carp: Biological Synopsis and Risk Assessment of an Introduced Fish, writes that the black carp are likely established in the USA.4
Impacts:
Silver carp are capable of consuming large quantities of phytoplankton. Nonetheless, potential effects of the silver carp introductions are difficult to assess. If stable breeding populations were to form and the number of individuals became abundant, shifts in food web structure could be expected. Although reported to consume mostly phytoplankton, and equipped with a highly specialized filtering apparatus, silver carp consume whatever form of plankton is available in its environment. Where phytoplankton is scarce this species will consume zooplankton (Spataru and Gophen, 1985; Burke et al., 1986). Consequently, increases in algal biomass in ponds stocked with silver carp, have been reported (Burke et al., 1986), so its ecological impacts are not always predictable. Spataru and Gophen (1985) reported declines in zooplankton biomass in Lake Kinneret, Israel, which they attribute to stocked silver carp. As is the case with most non-indigenous species, this species can transport diseases to new areas. Bocek et al. (1992) found silver carp to be an effective carrier of Salmonella typhimurium4
Economic impacts:
The Fish and Wildlife Service is supporting State and Interstate Management Plans to limit range expansion, abundance, and Economic impacts of Asian carp and other species. We also provide operating expenses for six Regional Panels (Great Lakes, Mississippi Basin, Western, Northeast, Gulf, and MidAtlantic) on Aquatic Nuisance Species. The Panels were established to identify priorities for activities in the Panel regions, coordinate aquatic nuisance species program activities in each region, and advise public and private interests on control efforts. The Fish and Wildlife Service is also leading the development of a National Management and Control Plan for Asian carp. The Plan should be completed by the end of 2004, and will provide coordinated direction for prevention, management, and control Activities targeted at Asian carp[3]
History:
Bighead, silver, grass, and black carp are native to Asia. Grass carp were first introduced into the United States in 1963, whereas bighead, silver, and black carp arrived in the 1970s. All four species escaped into the Mississippi River Basin, and all but the black carp are known to have developed self-sustaining populations. Bighead and grass carp were captured in the Great Lakes Basin, but there is no evidence of reproduction to date.3 Grass carp inhabit waters within and bordering 45 states, whereas bighead carp have been collected from 18 states, silver carp from 12 states, and black carp from only Illinois (some escaped from an aquaculture facility in Missouri). See the maps on the last page for more details on the distribution of the four species of Asian carp. Data from the Illinois Natural History Survey indicates that bighead carp abundance has been increasing exponentially in a portion of the Upper Mississippi River. The population has tended to double there every year. Bighead carp populations may be increasing at equally fast rates on portions of the Illinois and Missouri Rivers, while silver carp abundance may be increasing at similar rates in all of those rivers.
Control Measures:
Some 40 kilometers downstream, Asiancarp are steadily advancing toward Lake Michigan. Scientists fear that if these voracious fish get there, they could eventually upset ecosystems in all the Great Lakes. To block the attack, a consortium of researchers is testing an electric barrier that they hope will repel the carp when they arrive, likely later this summer. Asiancarpwill be the first challenge to the barrier, but not the last. Troublemakers are lined up on both sides of the barrier: The carp and other species further downstream are trying to breach the Great Lakes, and exotic fishes in the lakes could gain access to the entire MiSSiSSippi River system. "This canal is a choke point," says David Lodge of the University of Notre Dame in Indiana, who is not involved in the project. And that strategic location makes the barrier "vitally important." Despite limitations, it's also a promising model for how to prevent the flow of aquatic invaders between water bodies that were once naturally isolated from each other, Lodge says. As the fish draw nearer, researchers are still trying to figure out exactly how well the barrier will work--and how to make it stronger. 4 John Dettmers of INHS and Richard Sparks of the University of Illinois, Urbana-Champaign, have been testing surrogate fish, the naturalized common carp, against the real barrier. They outfitted 72 fish with antennae and placed them downstream of the barrier. Radio and acoustic receivers continuously monitor their position. Most of the carp don't probe the barrier, they say, and since November only one has crossed it. That happened on 3 April, at the same time a barge chugged past the barrier. When traffic is heavy, up to 20 barges pass through the canal in a day. Dettmers speculates that the fish might have been pulled along by the strong wash from the propellers as the barge maneuvered, or that the steel barge somehow weakened or altered the electric field. After the fish escaped, the researchers cranked up the strength of the electric field by 50%; no tagged fish have crossed since. However effective the barrier proves to be against the Asiancarp, researchers have long argued that it is not enough. For starters, they say, a second barrier is needed to catch any fish that might slip through, to allow maintenance, and to make the system more failsafe in case of freak weather or power outages--as happened in April. (Funds for a second barrier are included in the reauthorization of the invasive species act, now before Congress.) 4
ASIAN CARP
General Information:
Hypophthalmichthys molitrixThe Asian Carp or (Hypophthalmichthys molitrix) is a very compressed silvery scaled fish that are toothless.
Larger species have a stiff on the dorsal and anal fins as well as the end of its pectoral.
There have been reports of a silver carp caught that weighed in at 1260 mm. They are at large four feet long and can grow to an astonishing 80 to 100 pounds.[1]
Detailed Description:
Bighead and silver carp have reproductive requirements similar to those of striped bass. There is a real potential to establish a reproducing population of Asian carp in Lake Texoma which could be devastating to striped bass fishery and paddlefish recovery efforts.
The silver carp is a filter feeder, and possesses a remarkably specialized filtration apparatus capable of filtering particles as small as 4 µm. The gill rakers are fused into a sponge like filter, and an epibranchial organ secretes mucous which assists in trapping small particles. A strong buccal pump forces water through this filter. Silver carp, like all Hypophthalmichthys species, have no stomachs; they are thought to feed more or less constantly. Silver carp are thought to feed largely on phytoplankton; they also consume zooplankton and detritus. Because of their plankton-feeding habits, there is concern that they will compete with native planktivorous fishes, which include paddlefish Polyodon spathula, gizzard shad Dorosoma petenense and young fish of almost all species.[2]
The silver carp unlike any other sea creatures has little or no predators around where they were let out near the United States. Silver carp are only predators that have no known predators around where they were sent to from Arkansas. This invasive species is very harmful to the food chain and is not a benefit what so ever. Although silver carp are very aggressive and are “taking over” the seas near our country there are a few other species of Asian carp that were also sent here to maintain phytoplankton population but it back lashed.
Habitat and Distribution:
All the above except large-scale silver carp have been cultivated in aquaculture in China for over 1,000 years. Large-scale silver carp, a more southern species, is native to, and is cultivated in Vietnam. Grass, silver, bighead and black carps are known as the "Four Domesticated Fish" in China and are the most important freshwater fish species for food and Chinese medicine. Bighead and silver carps are the most important fish, worldwide, in terms of total aquaculture production [1] . Common carp and crucian carp are also common food fishes in China and elsewhere. Goldfish, on the other hand, are cultivated mainly as pet fish.4
Because of their prominence, and because they were imported to the United States much later than the other species of freshwater fish, the term "Asian carps" is often used in the United States with the intended meaning of only grass, black, silver, and bighead carps. In the United States Asian carps are considered to be nuisance invasive species. Of the Asian carps that have been introduced to the United States, only two (crucian and black carps) are not known to be firmly established. Crucian carp is probably extirpated.[2] However, since 2003, several adult, fertile, black carp have been captured from the Atchafalaya and other rivers connected to the Mississippi River.[3] Dr. Leo Nico, in the book Black Carp: Biological Synopsis and Risk Assessment of an Introduced Fish, writes that the black carp are likely established in the USA.4
Impacts:
Silver carp are capable of consuming large quantities of phytoplankton. Nonetheless, potential effects of the silver carp introductions are difficult to assess. If stable breeding populations were to form and the number of individuals became abundant, shifts in food web structure could be expected. Although reported to consume mostly phytoplankton, and equipped with a highly specialized filtering apparatus, silver carp consume whatever form of plankton is available in its environment. Where phytoplankton is scarce this species will consume zooplankton (Spataru and Gophen, 1985; Burke et al., 1986). Consequently, increases in algal biomass in ponds stocked with silver carp, have been reported (Burke et al., 1986), so its ecological impacts are not always predictable. Spataru and Gophen (1985) reported declines in zooplankton biomass in Lake Kinneret, Israel, which they attribute to stocked silver carp.
As is the case with most non-indigenous species, this species can transport diseases to new areas. Bocek et al. (1992) found silver carp to be an effective carrier of Salmonella typhimurium4
Economic impacts:
The Fish and Wildlife Service is supporting State and Interstate
Management Plans to limit range expansion, abundance, and
Economic impacts of Asian carp and other species.
We also provide operating expenses for six Regional Panels
(Great Lakes, Mississippi Basin, Western, Northeast, Gulf, and
MidAtlantic) on Aquatic Nuisance Species. The Panels were
established to identify priorities for activities in the Panel
regions, coordinate aquatic nuisance species program activities in
each region, and advise public and private interests on control
efforts.
The Fish and Wildlife Service is also leading the development of a
National Management and Control Plan for Asian carp. The Plan
should be completed by the end of 2004, and will provide
coordinated direction for prevention, management, and control
Activities targeted at Asian carp[3]
History:
Bighead, silver, grass, and black carp are native to Asia. Grass carp
were first introduced into the United States in 1963, whereas bighead,
silver, and black carp arrived in the 1970s. All four species escaped into
the Mississippi River Basin, and all but the black carp are known to have
developed self-sustaining populations. Bighead and grass carp were
captured in the Great Lakes Basin, but there is no evidence of reproduction to date.3
Grass carp inhabit waters within and bordering 45 states, whereas
bighead carp have been collected from 18 states, silver carp from 12
states, and black carp from only Illinois (some escaped from an
aquaculture facility in Missouri). See the maps on the last page for more
details on the distribution of the four species of Asian carp.
Data from the Illinois Natural History Survey indicates that bighead
carp abundance has been increasing exponentially in a portion of the
Upper Mississippi River. The population has tended to double there
every year. Bighead carp populations may be increasing at equally fast
rates on portions of the Illinois and Missouri Rivers, while silver carp
abundance may be increasing at similar rates in all of those rivers.
Control Measures:
Some 40 kilometers downstream, Asian carp are steadily advancing toward Lake Michigan. Scientists fear that if these voracious fish get there, they could eventually upset ecosystems in all the Great Lakes. To block the attack, a consortium of researchers is testing an electric barrier that they hope will repel the carp when they arrive, likely later this summer.
Asian carp will be the first challenge to the barrier, but not the last. Troublemakers are lined up on both sides of the barrier: The carp and other species further downstream are trying to breach the Great Lakes, and exotic fishes in the lakes could gain access to the entire MiSSiSSippi River system. "This canal is a choke point," says David Lodge of the University of Notre Dame in Indiana, who is not involved in the project. And that strategic location makes the barrier "vitally important." Despite limitations, it's also a promising model for how to prevent the flow of aquatic invaders between water bodies that were once naturally isolated from each other, Lodge says. As the fish draw nearer, researchers are still trying to figure out exactly how well the barrier will work--and how to make it stronger. 4
John Dettmers of INHS and Richard Sparks of the University of Illinois, Urbana-Champaign, have been testing surrogate fish, the naturalized common carp, against the real barrier. They outfitted 72 fish with antennae and placed them downstream of the barrier. Radio and acoustic receivers continuously monitor their position. Most of the carp don't probe the barrier, they say, and since November only one has crossed it. That happened on 3 April, at the same time a barge chugged past the barrier. When traffic is heavy, up to 20 barges pass through the canal in a day. Dettmers speculates that the fish might have been pulled along by the strong wash from the propellers as the barge maneuvered, or that the steel barge somehow weakened or altered the electric field. After the fish escaped, the researchers cranked up the strength of the electric field by 50%; no tagged fish have crossed since.
However effective the barrier proves to be against the Asian carp, researchers have long argued that it is not enough. For starters, they say, a second barrier is needed to catch any fish that might slip through, to allow maintenance, and to make the system more failsafe in case of freak weather or power outages--as happened in April. (Funds for a second barrier are included in the reauthorization of the invasive species act, now before Congress.) 4
REFERENCES
[1] Fisheries commission. "Hypophthalmichthys molitrix (Valenciennes, 1844)."
http://nis.gsmfc.org/nis_factsheet.php?toc_id=189. 21 Nov. 2003.
panel on aquatic invasive species. 12 Nov. 2008 <http://nis.gsmfc.org/
nis_factsheet.php?toc_id=189>.
[2] Wikipedia. "Silver Carp." www.Wikipedia.org. 20 Oct. 2008. 13 Nov. 2008
<http://en.wikipedia.org/wiki/Silver_carp>.
[3] Us fish and wildlife service. "Asian Carp- An aquatic nuisance species."
conserving americas fisheries. 1 Mar. 2004. 14 Nov. 2008
<http://www.asiancarp.org/Documents/AsianCarp.pdf>.
4 Stokstad, Erik. "Can well-timed jolts keep out unwanted exotic fish? In a desperate bid to prevent the spread of invasive fish, researchers have erected an unprecedented barrier that's nearing its first real test. (Invasive Species)." Science. 301. 5630 (July 11, 2003): 157(2). Student Resource Center - Gold. Gale. Stroudsburg High School. 20 Nov. 2008 <http://find.galegroup.com/srcx/infomark.do?&contentSet=IAC-Documents&type=retrieve&tabID=T002&prodId=SRC-1&docId=A105769949&source=gale&srcprod=SRCG&userGroupName=stro53037&version=1.0>.